1. Field of the Invention
The present invention relates to a copying apparatus with an automatic document feeder, and, more particularly, to a copying apparatus having a composite copying function capable of effecting transfer of images in plural number of times onto one side of a single sheet, and a double-side copying function capable of effecting transfer of images onto both the surface and the back.
2. Description of the Prior Arts
A copying apparatus, which has realized transfer of a plurality of images of a plurality of documents to a copy sheet, has recently been developed. For instance, the U.S. Pat. No. 4,537,497 discloses a copying apparatus providing the double-side copying function to conduct the copying to both sides of a copy sheet and the composite copying function to conduct a plurality of copyings to a single side of a copy sheet. For the double-side copying or composite copying operation, a copy sheet, which has been supplied from a cassette to form images thereon through an image forming section and an image fixing section, is sent to an intermediate tray and then sent again therefrom to the image forming section through a transporting section. The copying apparatus of this type provides a transparent table for supporting a book type document and a document tray for supporting a sheet type document and moreover provides a light source to irradiate the book type document through the transparent table and another light source which irradiates the sheet type document transported from the document tray.
The U.S. Pat. No. 4,705,393 provides a document feed unit which is attached to the position of transparent document support table at the upper part of the apparatus body, a document supplying unit which transports a sheet type document to the document feed unit and a reverse unit which accommodates, in the interrupt copying mode, a document transported from the copying position on the document support table. Upon completion of the interrupt copying, the relevant document is automatically transported reversely to the copying position from the accommodating position within the reverse unit to realize the copying based on the document. For the copying of both sides of document, namely, for respective copyings of images recorded to both sides of a sheet type document, after the copying of image on the one side of document, the document is transported to the reverse unit, the document sent from the reverse unit is then placed upside down and transported again to the copying position on the document support table.